Deformable or elastic accumulator



Feb. 22, 1944. J.,MERC|ER DEFOR MABLE OR ELASTIC ACCUMULATOR Original Filed Sept. 13, 1938 It A mv'ENToR JEAN MERCI ER Patented Feb. 22,1944

UNITED STATES PATENT OFFICE Original application September 13. 1938, Serial No. 229,641, now Patent No. 2,317,395, dated April 27, 1943.

Divided and this application July 25, 1942, Serial No. 452,363. In France December 10, 1937 2 Claims.

In my co-pending application 229,641 filed September 13, 1938, I have described a deformable or elastic accumulator and retained claims in that application that are generic to that modification.

This application has been drawn to comply with the original requirement for division and the claims herein are drawn to the modification shown in the drawing of this application.

The present invention pertains to liquid storage devices and more particularly to a container in which a source of pressure is applied to the liquid being stored.

Storage devices of this type generally consist of a container to be filled with the liquid and of a rubber bag or the like inserted in said container and filled with a gas under pressure. When liquid is supplied to the container by a suitable source of liquid under pressure the bag will be compressed until the pressure of the gas inside said bag reaches the value of the pressure under which the liquid is supplied. Thereafter, liquid can be Withdrawn from the storage device under progressively decreasing pressure.

When functioning with a liquid operated system or unit the storage device will generally not be used to its full capacity, that is, the bag will generally not be required to expand so as to expel all the liquid from the container. However, when storage devices are installed on vehicles or aircraft it is of great interest that, at least in an emergency, the greatest possible amount of liquid can be expelled from the container so as to be available for the operation of the hydraulic devices. Moreover, it is generally required that the last portions of liquid leaving the container be available under considerable pressure, as, for instance, 1400 lb. per square inch or more. Consequently, the bag must be filled with a gas under high pressure.

On the other hand, the bag must possess great flexibility so that it can follow without appreciable resistance the frequent compressions and expansions required for the normal operation of the storage device. The bag must, consequently, be made of a material which is incapable of resisting the compression and expansion due to the gas-pressure.

It is a shortcoming of storage devices of this type that the bag, as soon as it fails to be completely supported by the liquid or by the wall of the container, is liable to be torn. Whenever it is attempted to expel substantially all liquid from the container, this shortcoming will cause injury to the bag. In most cases the bag is injured because it is forced into the passage through which liquid is admitted to or discharged from the container.

It is an object of the present invention to protect the bag from injury by means of a safety valve.

According to a feature of the present invention the bag is attached to one end of the container. At the opposite end it carries valve means connecting the inside of said container with the inside of said bag. Said valve means include a movable valve element and yielding means urging said movable element against a seat whereby liquid will be prevented from entering into said bag. Whenever the pressure inside said bag exceeds the pressure of the liquid surrounding said bag, by a predetermined value, said movable valve element will be lifted from its seat so as to permit a certain amount of gas to escape into said container.

Further features of the present invention may be gathered from the following description of an embodiment of the present invention given by way of example and illustrated in the accompanying drawing:

In the drawing, there is a container l, a bag 5, attached to one end of the container at 6. At its opposite end, bag 5 carries a valve comprising a cylindrical portion 4 and a chamber l0. Chamber l0 communicates through orifices H with the inside of container l and through a conduit 8 in portion 4 with the inside of bag 5. A ball valve 1 adapted to close conduit 8 is urged against its seat by a spring 9.

The pressure of the liquid inside container I and the force of spring 9 tend to force ball 1 against its seat, thus preventing access of liquid into the interior of bag 5.

The force of spring 9 may be relatively small, so that pressure exerted by the same on ball I may not be superior to 50-200 grams per square centimeter. This will insure prompt opening of the valve and discharge of gas from the bag whenever the liquid in container I fails to exert a sufficient pressure on ball I.

The valve according to the present invention afiords means to discharge gas from said bag whenever the difference in pressure inside and outside said bag exceeds a value to which said bag can resist.

The present application is a division of my copending application Serial No, 229,641, filed September 13, 1938, which has matured into Patent No. 2,317,395, granted April 2'7, 1943.

The foregoing description is not intended to limit the scope of the present invention which does not depart from, but rather extends to all changes, modifications and equivalents comprehended within the scope of the appended claims.

I claim:

1. An accumulator for the storage of liquid which comprises, in combination, a rigid container adapted to be supplied with said liquid and a flexible deformable elastic bag in said container fixed at one end thereto and filled with gas under pressure, valve means attached to said bag at a point opposite to the end where it is attached to said container, said valve means comprising a movable valve element subjected on oneside to the pressure of said liquid inside said container and on the opposite side to the pressure of said gas inside said bag, said valve means being adapted to prevent outflow of said gas from said ba except when the pressure of said liquid is inferior to that of said gas and the difference exceeds a predetermined value.

2. An accumulator for storage of pressure fluid which comprises, in combination, a rigid container, a passage for. liquid in one portion of said container, a deformable inflated bag in said container secured to a portion thereof opposite said passage, safety valve means associated with said bag, said means includinga member, secured to the portion of said bag adjacent said passage when said bag is expanded, a casing rigid with the end portion of said member at the outside of said bag, a bore extending throughout said 'member and opening, at one end thereof, into the interior of said bag and, at the other end, into said casing, a valve seat formed in said member surrounding the opening of said bore into said casing, a spring loaded movable valve element inside said casing and being adapted to obstruct said bore when being applied against said seat, and, at least, one opening in said casing to afford communication between the interior of the same and the interior of said container.

J EAN' MERCIER. 

